I suspect I'm not understanding this question very well so I not going to answer the question directly as I can't.

But (unless things have moved on without me knowing) I thought an SPDIF cable is specifically for carrying a digital optical signal out from a TV; it is an output from a TV not an input.

Things may have moved on but I can't really think why you might want to input a digital optical signal into a TV because the sound reproducing circuitry and speakers in any TV is, to put it politely, 'basic' and any improved sound quality would be negated when it came from the TV speakers. Or have I got the question wrong and you are talking about an output signal from a TV

Quote:

Originally Posted by TheClash

does an SPDIF cable only send audio signals to the TV if so why not just use a HDMI? is it both video and audio and if so how do you get TV to recognise SPDIF input?

Many modern TVs have SPDIF out connectors, they also have HDMI outputs/inputs the clue in HDMI is the HD standing for High Definition, it could be compared to ADSL broadband which uses copper cable and high speed fibre broadban which use Optical cable. HDMI uses copper and SPDIF is usually fibre.

Also HDMI connections/cables offer input and/or output signals of both video and audio via one convenient interface, providing you have the compatible devices and cables (and in some set ups HDMI switching). But! Although HDMI signals were at one time the pinnacle of quality in both sound and video, things have moved on.

Now, surround sound systems seek to provide an even more improved sound matching that previously confined to professional sound studios. These were the places where optical cables were used to achieved near perfect sound reproduction. So now many big TV names also supply surround sound systems for their TVs and consequently in the war to provide better than the competitor optical fibre cables (SPDIF) came on the scene for the sound output connection to their surround sound system.

Next came the 'sound bar' for anybody who didn't want or couldn't have the surround sound system(s) but were still unhappy with the rubbish sound from a flat screen TV's tiny speakers. It was then a logical move to include an SPDIF input for the sound bar.

So to come back to your question, with the right connector/adapter you could isolate and connect to the audio output in your HDMI connector and input that into audio jack of a sound bar or surround sound system but supposedly for even better quality sound, if your TV has an SPDIF output then by using the special SPDIF cable to the SPDIF input of your audio system better and clearer sound quality will (in theory) be acheived. (but the actual level of improved sound will usually depend on the quality of the the equipment)

One of the reasons I use an optical fibre 'cable' to link the TV to the Audio amp is that it cured a ground loop that was causing a lot of hum from the speakers. The cable came from Poundland, and cost £1, for a metre long one.

I use an optical digital audio cable out from the TV to a sound bar, then turn off the TV's internal speakers. The sound is then controlled from a remote (sound bar) to change from surround to direct speech, whichever takes your fancy. Sound quality is far superior.

I use an optical digital audio cable out from the TV to a sound bar, then turn off the TV's internal speakers. The sound is then controlled from a remote (sound bar) to change from surround to direct speech, whichever takes your fancy. Sound quality is far superior.

With a high speed HDMI cable, the sound bar will auto switch on and off, plus better sound is transmitted, I tested an optical cable, much flatter sound.

My soundbar is a Sony, connected to a Sony TV via the ARC out.
MeesterChris is correct. An HDMI connection gives far superior sound to the optical one and the soundbar is automatically turned on by the TV. With the optical connection I have to turn it on. If the TV has no ARC out then you need to connect both HDMI and optical.

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